The British Columbia government is calling in external experts to take a deeper look at a possible connection between severe glaucoma and a widely used type of eye injection after some of the province’s top ophthalmologists warned that toxins may be leeching into the medication in that province.
B.C.’s Ministry of Health, the Provincial Health Services Authority (PHSA), and retinal specialists are also promising to inform patients of the potential risk that the sight-saving injections could lead to glaucoma requiring surgery.
“Patient safety is paramount,” B.C. Health Minister Adrian Dix said in an interview on Friday. “It’s patients who need independent reviews and that’s why I’ve acted in this way.”
Mr. Dix said the “overwhelming consensus" of the advice he received from a group of 29 retinal specialists and two glaucoma specialists was that the province should continue to offer publicly funded eye injections to about 20,000 patients because the injections are an effective treatment for wet age-related macular degeneration, once a common cause of irreversible blindness.
Mr. Dix’s announcement came on the same day that the B.C. Society of Eye Physicians and Surgeons (BCSEPS) had set as a deadline for action in a legal letter it sent to the province last week that demands it halt the use of one type of the eye drug.
As The Globe and Mail first reported on Wednesday, the professional society for the province’s eye doctors warned that thousands of retinal-disease patients in B.C. could be at elevated risk for “severe glaucoma and peripheral blindness,” possibly because of toxins leeching out of the syringes when one formulation of the drug is used.
A group of glaucoma specialists had already warned the province of an unexpected spike in severe glaucoma cases in a February e-mail, also obtained by The Globe.
On Tuesday night, the B.C. Ministry of Health and Maureen O’Donnell, executive vice-president for clinical policy, planning and partnerships at the PHSA, said officials had already spent more than a year studying the potential problem, including conducting a supply-chain review. They found no evidence of toxins seeping into the injectable drugs, Dr. O’Donnell said.
Asked why his government did not make the glaucoma specialists’ concerns public earlier, Mr. Dix said the issue was only brought to his attention about 10 days ago.
“You can see my response [now] and that response wasn’t long delayed,” he said.
The province is now asking the BC Centre for Disease Control and the Public Health Agency of Canada to “review the data from the program and wider research literature to identify any risks or new trends," the Ministry of Health said in a statement.
At the centre of the controversy is a drug called Avastin, one of a handful of anti-vascular endothelial growth factor, or anti-VEGF, eye injections that can halt or reverse some retinal diseases, including wet macular degeneration.
Originally developed as a cancer drug, Avastin, or bevacizumab, is not Health Canada-approved to treat retinal diseases, but doctors often use if off-label for that purpose because it is very similar to Lucentis, a competitor that is 10 times more expensive than Avastin.
The primary concern is that Avastin – which is sold in large vials geared toward oncology patients – has to be split, or compounded, at a pharmacy into smaller doses for eye injections, creating a risk for contamination.
There is robust clinical-trial evidence that Avastin is as effective and safe as Lucentis, also known as, ranibizumab, but Avastin’s maker has not applied to Health Canada or other regulators to have it approved for retinal diseases.
Genentech, part of the Swiss Pharmaceutical giant Roche, developed both drugs, and Roche still owns the rights to both in the lucrative United States market. (Novartis distributes Lucentis in Canada.)
More than a decade ago, the B.C. government recognized it could save a significant amount of public money if ophthalmologists could be convinced to prescribe Avastin off-label instead of Lucentis or the other Health-Canada-approved anti-VEGF drugs that would later come to market.
The B.C. government, in co-operation with a few dozen retinal specialists, in 2009 launched the B.C. Provincial Retinal Diseases Treatment Program under which retinal specialists agreed to use cheaper Avastin for 85 per cent of total anti-VEGF treatments in the province.
Dr. Derek Godinho, the president of the Association of British Columbia Retina Specialists, was not available to comment Friday. Representatives of BCSEPS, the professional society whose legal letter prompted the independent investigation, also declined to comment.
Although some other provinces, including Alberta, Nova Scotia, New Brunswick and Manitoba publicly insure Avastin for retinal diseases, none has moved as aggressively as B.C. in promoting the lower-cost option. In Nova Scotia, for example, only 16 per cent of anti-VEGF injections were performed with Avastin in 2018-19.
In Ontario, where Avastin is not publicly funded for any retinal diseases, Lucentis was the top line in the government’s drug budget in 2017.